Improvement in grinding-mills for bark



R. H. SHULTIS. Grinding-Mill for Bark.

No. 206,494. Patented July 36, I878,

Fig.1.

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INVENTORI ATTEST, RM HAY/mm,

MPETERS, PHOTO-UTHOGRAPHER, WASHINGTON u C UNITED STATES PATENT OFFICE.

ROBERT H. SHULTIS, OF KINGSTON, NEW YORK.

IMPROVEMENT IN GRINDING-MILLS FOR BARK.

Specification forming part of Letters Patent No. 206,494. dated July 30,1878; application filed May 17, 1878.

1'0 all whom it may concern:

Be it known that I, ROBERT H. SHULTIs, of Kingston, in the county ofUlster and State of New York, have invented certain Improvements inGrinding-Mills for Bark and similar substances, of which the followingis a specification:

This invention relates most especially to mills for grinding orpulverizin g bark for tannin g purposes; and consists, essentially, inthe construction and arrangement of the grinding parts and surfaces andtheir combinations with other parts of the mill.

In the drawings, Figure l is avertical midsection of amill embodying myimprovements; and Figs. 2, 3, and 4. are detail views, illustrating theconstruction of the various parts.

A is a hopper, made wholly or partially of cast metal; andB is a centralcone or shell, in which is the hearing for the shaft 0. The parts AB arecast in one piece and connected by ties to a.

The parts A D are circular in plan, and between their lower edges is anannular space for the runner. The casting is put in the boring-machine,and the shaft-bearin g bored out true; and while in place recessed seatsb b are turned truly concentric therewith in both walls 'of the annularspace for the runner to receive chilled or otherwise hardenedgrinding-sections 0 c. This construction insures the concentricity ofthe grinding-surfiiccs, which is of the utmost importance.

I prefer to turn the seats I) b at right angles to the plane of thebottom edge of the casting or parallel to the bore, as this constructioninsures greater accuracy, and is efl'ected with greater facility, thanwhen turned to a bevel, as is usual in such machines. If a bevel isdesired for the grinding-surfaces, it can then be attained by making thesections 0 c thicker at one edge than at the other.

The sections 0 c are of cast-steel or chilled iron, and are cast withthe proper curve to fit into their recessed seats I) I). They are ofuniform length and maybe cast from the same pattern, and are aliquots ofthe circle in which they are set. Each end of each section has formed init a beveled recess, (1, and when the sections are put in place andabutted together the head of the retaining-screw c rests in the openingformed by the two ac jacent recesses, and holds the sections firmly intheir seats. Fig. 4 shows an elevation and horizontal section of one ofthe grinding-sections c and a part of another, showing distinctly thetoothing of the surface and the method of fastenin D is a breaker of theordinary kind, keyed to the shaft 0, and E is a spider on the shaft,which may be driven by lugs g engaging recesses in its boss.

F is a rim cast upon the spider-arms and faced up truly concentric withits bore.

G is a double-faced ring-grinder, of chilled iron or cast-steel, whichis bolted down upon the ring F of the spider, and rotates between thegrinding-faces c c. Fig. 2 shows the toothing on the faces of this ring,and Fig. 3 the under side of the ring and the top of the rim F on whichit sits.

To prevent the ring from slipping on its seat, and to take the strainoff the fastening bolts h, I provide raised parts c' i on the rim F toengage the recesses or hollows jj in the ring G. The ring has a sectionsomewhat like an inverted V, and when in place it forms, with thesections 0 0, two trough-shaped annular cavities to receive the barkfrom the breaker, as seen in Fig. 1.

The screws h are preferably cast in the ring, and when the latter is inplace on the rim these pass through holes, and receive nuts on theirextremities, as shown.

The mill is provided wit-han ordinary bowl or receiver, II, and the armsof the spider are made to conform somewhat to the shape of the same, soas to drive the ground bark out at the aperture k.

The usual adjusting devices maybe applied to lower or raise the grinderand regulate the fineness of the product of the mill.

The grinding-sections c c and the ring 0: must be of very hard material,and I prefer to make them of chilled iron; but they may be ofcast-steel, or be case-hardened; or the sections may be of cast-steel.and the ring-grinder of chilled iron.

I claim- 1. In a grinding-mill, the combination of the grinding-surfacesc c, the spider E, the rim F of the spider provided with raised segmentsand bolt-holes through. the rim between them,

and the grindingring G, provided with segmental or partitioned recesseson its under side to engage the segments bolts to engage the bolt-holes,substantially as set forth.

2. The sections 0 a, of hardened cast metal, provided with beveledrecesses d d intheir ends to receive the heads of the fasteningscrews,substantially as set forth.

In witness whereof I have hereunto si ned my name in the presence of twosubscribing on the rim, and Witnesses.

It. H. SHULTIS.

\Vitnesses:

J. E. .OSTRANDER', M. Ti TRUMPBOUR.

